Many people, mainly those who have lived around the ocean or who have visited the ocean on more than one occasion, refer to the ocean's tides as the “breath of the earth” because in some ways, the back and forth motions of the ocean’s waves crashing on the shore and then sinking back into the giant body of water resemble a human being taking in oxygen into their lungs in deep breaths. In reality,the scientific definition for the ocean's tides are the cyclic rise and fall of the sea water. In other words, it is the periodic rising and falling of the ocean’s water according to where the moon and sun are and what time of day it is. The gravitational attraction between the earth and the moon is what causes these tides. The moon strains to grab onto anything on the earth to make it come closer. The earth is able to hold on to everything except for water because it is always moving; this allows the moon to pull it just enough to make waves. Waves are also caused from wind and moving currents but tides and waves are two different things. The tides are not directly caused from the pull of the moon. The moon pulls upward while the earth pulls downward. The moon as a slightly larger pull than the earth does so it causes the water to move back and forth on earth. Even though this is a true fact, the sun’s gravitational force on earth is about 46 percent that of the moon. This means that even though the moon is not the only factor playing into tides, it is the main factor. The type of gravitational pull that causes tides, and the attractions, is called Tractive Force.
History of The Tide
Tides have always been a topic of interest to many people according to the research that many scientists have done. The scientists have found research from earlier scientists that trace back all the way to 325 B.C. There has to be a reason why all these scientists have found such a great interest in tides for such an expanded time periods.
Selecus
The tides have always been around as far as people can tell and were that everyone could, and did, look at almost everyday of their lives. It took more than the average person to actually walk by one day and wonder why the tides work, how they function and what the tides purpose of being on earth was. Scientists have traced back and according to many of them, tides research all started with a Greek geographer and explorer name Pytheas of Massalia. He seems to be the first person in history to tie together that the moon phases are related to the ocean's tides. After Pytheas, down the road many other scientists and astronomers, or even the average person, slightly or largely altered the information we know today about the tides. Many of these people include Selecus of Seleucia, Pliny the elder, Philostratus, Bede, and Al-Kindi. Selecus proved that the tides are cause by the moon but he had thought that the pneuma mediated the reaction between the two. He had noticed that to where a person was standing in the world, the tides would be different. He had also noticed that the time on Earth played a part on how the tides work and operate. For example, if you were standing on one of the beach's shores in Mexico, the tides would be completely different than if you were to be standing on one of the beach's shore in Australia. Selecus was the first to record that the tides and lunar attractions worked with each other. Also, he was the first person ever to link the height of the tides and the Moon's position relative to the Sun's location (due to Earth) together. Pliny the Elder had recorded many tidal observations by studying them daily and ended up changing a few of earlier scientists' believes,observations, and incorrect information they had gathered about the tides. Pliny noted that the spring tides were either a few days before or after a new moon or full moon occurred. He had also observed that the tides were at their highest when it was approaching and equinox. Bede had described how the rising tides on one coast of the Bristish Isles coincided with the fall on the other side of the British Isles. Around the time of 730 AD, he had also described the time progression of high water along the North Umbrian coast in Europe.
Credit To: NOAA'S website
Types of Tides and When They Occur
Everyday on Earth there are four tides through out the day. Those tides include two high tides and two low tides. The ocean is always going back and forth between high tide and low tide and will eventually go back to a high tide. There are about 12 hours and 25 minutes between every high tides. Ocean waves can transport energy over very large distances but the water its self
Credit to: howthingswork.com
does not move. It stays in the same location through out the whole day but it does move up and down, in a bobbing motion. One wave's motion is completely independent of any other wave's motion. Another thing, when two groups of waves meet, they will pass right through each other but they can also cancel each the other wave out or ass up as they pass. This is called superposition. When they cancel each other out they are lining up with the trough of another wave, this is called destructive interference. When they add up, the waves have to line up crest to crest or trough to trough almost perfectly. This interaction is called constructive interference. There is more than one type of tide. You can tell this is an obvious, but important observation by looking at how the high water is in morning, then in the afternoon, then in the evening. The water will either be higher or lower than the previous time it was observed that day. Spring tides, or otherwise known as strong tides, happen when the sun and the moon are on the same side of the Earth or opposite sides of the Earth. In other words, spring tides happen when there is a new moon phase or a full moon phase occurring. There is also a different type of tide called neap tides. Theses tides occur when the moon is in its quarter phases. The sun and the moon are working at right angles and this point. A very rare type of tide that occurs, at the most, about every one and a half years is called a proxigean tides. Proxigean tides occur when the moon is unusually close to the Earth and is in its new moon phase. No matter what type of tide it it, if the tides are coming towards the shore it called a flood current. Tides heading away from the shores are called eb currents. Although tides and waves are not the same thing, they do tie into each other and play a big part in how the other one acts. The crest is the very top of the wave and the trough is the hollow between two crests. The vertical distance between the crest and the trough is the wave height while the wave length is the horizontal distance between any one given point on a wave and the corresponding point on the next side. Wave steepness is the ratio of the wave's height and length. The amplitude is the maximum vertical displacement of the sea surface from still water level. The time it takes for one complete wave length to pass a stationary point is called the period. The wave speed is the velocity that a certain wave has traveled.
Parts of the tides:
Crest- Top of the wave
Trough- Hollow between two crests
Wave Height- Vertical distance between crest and trough
Wave Length- Horizontal distance between any point on wave and point on next side
Wave Steepness- Ratio of wave's height and length
Amplitude- Maximum vertical displacement of sea surface from still water level
Period- Time it takes for one whole wave to pass stationary point
Wave Speed- Velocity that a wave has traveled
How the Tides Affect Us
A very powerful and known effect of tides on people is the fact that it can sometimes put people or buildings in danger. Spring tides or High tid
es are usually the cause for such danger. When the tides get so high and strong they can sometimes flood houses, ruin cities, and can even kill or seriously injury a human by drowning.
Credit To: World's Natural Wonders website
Although, this not a common occurrence and only happens every once in a while, cautions should still be taken. It would take a very strong storm or powerful tide to cause that much damage. A new effect on humans that is still being developed is the fact that it can be used for energy. People are still working on this but it seems to be a great way to get natural energy. The most common effect that the tides have on humans is the behavior of the sea life. Many different species of sea life depend on the tides for survival, especially the species that live closer to the shore and beaches. Humans use the sea life as a source of food and have to use the movement of the tides to their advantage. Fisherman pay special, close attention to what the tides are going to be doing when they go on their next fishing trip so that they know where to look, what type of sea life will be where, when to cast nets, and most importantly, when they should go out. Another effect on humans is the fact that if you tie your boat to a dock, you have to pay attention to when the tides come in and out so your boat does not get stuck in mud because of the fact that they move so much. This plays in the fact that only certain docks can be used on certain days and at certain times. Many people how use a boat have to use a schedule to know when they can use a certain dock. Construction of docks can rely on when the tides come and and go out. If a tides comes in only a few times a year, there is no point in building a dock there but if a tide comes in many times a year, or even many times a day, then it would probably be necessary to build a dock there for boaters to use.
Table of Contents
In General
Many people, mainly those who have lived around the ocean or who have visited the ocean on more than one occasion, refer to the ocean's tides as the “breath of the earth” because in some ways, the back and forth motions of the ocean’s waves crashing on the shore and then sinking back into the giant body of water resemble a human being taking in oxygen into their lungs in deep breaths. In reality,the scientific definition for the ocean's tides are the cyclic rise and fall of the sea water. In other words,
History of The Tide
Tides have always been a topic of interest to many people according to the research that many scientists have done. The scientists have found research from earlier scientists that trace back all the way to 325 B.C. There has to be a reason why all these scientists have found such a great interest in tides for such an expanded time periods.
The tides have always been around as far as people can tell and were that everyone could, and did, look at almost everyday of their lives. It took more than the average person to actually walk by one day and wonder why the tides work, how they function and what the tides purpose of being on earth was. Scientists have traced back and according to many of them, tides research all started with a Greek geographer and explorer name Pytheas of Massalia. He seems to be the first person in history to tie together that the moon phases are related to the ocean's tides. After Pytheas, down the road many other scientists and astronomers, or even the average person, slightly or largely altered the information we know today about the tides. Many of these people include Selecus of Seleucia, Pliny the elder, Philostratus, Bede, and Al-Kindi. Selecus proved that the tides are cause by the moon but he had thought that the pneuma mediated the reaction between the two. He had noticed that to where a person was standing in the world, the tides would be different. He had also noticed that the time on Earth played a part on how the tides work and operate. For example, if you were standing on one of the beach's shores in Mexico, the tides would be completely different than if you were to be standing on one of the beach's shore in Australia. Selecus was the first to record that the tides and lunar attractions worked with each other. Also, he was the first person ever to link the height of the tides and the Moon's position relative to the Sun's location (due to Earth) together. Pliny the Elder had recorded many tidal observations by studying them daily and ended up changing a few of earlier scientists' believes,observations, and incorrect information they had gathered about the tides. Pliny noted that the spring tides were either a few days before or after a new moon or full moon occurred. He had also observed that the tides were at their highest when it was approaching and equinox. Bede had described how the rising tides on one coast of the Bristish Isles coincided with the fall on the other side of the British Isles. Around the time of 730 AD, he had also described the time progression of high water along the North Umbrian coast in Europe.
Types of Tides and When They Occur
Everyday on Earth there are four tides through out the day. Those tides include two high tides and two low tides. The ocean is always going back and forth between high tide and low tide and will eventually go back to a high tide. There are about 12 hours and 25 minutes between every high tides. Ocean waves can transport energy over very large distances but the water its self
Parts of the tides:
How the Tides Affect Us
A very powerful and known effect of tides on people is the fact that it can sometimes put people or buildings in danger. Spring tides or High tid
es are usually the cause for such danger. When the tides get so high and strong they can sometimes flood houses, ruin cities, and can even kill or seriously injury a human by drowning.
Although, this not a common occurrence and only happens every once in a while, cautions should still be taken. It would take a very strong storm or powerful tide to cause that much damage. A new effect on humans that is still being developed is the fact that it can be used for energy. People are still working on this but it seems to be a great way to get natural energy. The most common effect that the tides have on humans is the behavior of the sea life. Many different species of sea life depend on the tides for survival, especially the species that live closer to the shore and beaches. Humans use the sea life as a source of food and have to use the movement of the tides to their advantage. Fisherman pay special, close attention to what the tides are going to be doing when they go on their next fishing trip so that they know where to look, what type of sea life will be where, when to cast nets, and most importantly, when they should go out. Another effect on humans is the fact that if you tie your boat to a dock, you have to pay attention to when the tides come in and out so your boat does not get stuck in mud because of the fact that they move so much. This plays in the fact that only certain docks can be used on certain days and at certain times. Many people how use a boat have to use a schedule to know when they can use a certain dock. Construction of docks can rely on when the tides come and and go out. If a tides comes in only a few times a year, there is no point in building a dock there but if a tide comes in many times a year, or even many times a day, then it would probably be necessary to build a dock there for boaters to use.
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Hopewell Rocks
Bay of Fundy
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